Adding flash memory to the ESP32 and Mongoose driver support


Hi All, I’m currently using the ESP32 WROOM-U32 module which only has up to 16MBytes flash on the module. The datasheet for the ESP32 basically says that this is the max. However, I see in the API section of this website that there is a VFS driver to support the Winbond W25N01 and W25M02 chips, which are much bigger than 16MBytes.

If the driver works I could disable the module’s flash and add one of these chips, but I’m confused. If the MPU has memory mapping issues beyond 16MBytes how can this work? Is it tested? I currently want to replace an SPI connected SD card.

Thanks very much.


Never mind, apparently I misread the datasheet and the limit only applies to the cache.


AFAIK, you can’t disable the internal flash and replace it with an external one.
The external SPI flash can be used as a storage device.


It looks like I can add a flash chip, I ordered some 1Gb Windond flash chips and I’ll test when they arrive.